Zero Trust is a cybersecurity model based on the principle that no user, device, or system is trusted by default—whether inside or outside a network. Instead of granting broad access after initial authentication, every request to access a resource is continuously verified using identity, device security, location, and behavior. Access is limited to only what is necessary (least privilege), and trust is never permanent; it is evaluated in real time. This approach reduces the risk of lateral movement and data breaches by assuming that threats may already exist within the environment and enforcing strict, granular controls at every level.

Minimal Real-World Architecture Example

Stack:

• Identity: Entra ID
• Device: Intune
• Access: Zscaler ZTNA
• Logging: Sentinel
• Privilege: CyberArk

Flow:

1. User logs in → MFA enforced
2. Device checked → compliant
3. Requests app → ZTNA broker
4. Policy evaluated → allowed
5. Activity logged → monitored

Common Mistakes

• Keeping VPN (breaks Zero Trust)
• Not enforcing MFA for admins
• Ignoring service accounts
• No visibility/logging
• Over-permissioned roles